Abstract In the mechanical vapor recompression (MVR) treatment of landfill leachate, scaling in the evaporator and heat exchanger poses a serious problem. This study explored the reasons for such scaling and proposed acid or ion-exchange pre-treatments to reduce the alkalinity of the landfill leachate nanofiltration concentrate (LLNC) to prevent scaling. The feasibility of these two methods was evaluated and the technical and economic parameters for application were obtained via experiments. A large amount of HCO3- in the LLNC was the main cause of scaling. The acid addition experiment and field application demonstrated that this method could prevent fouling problems. The cost of acid addition was USD 0.18/t. LLNC pre-treatment by ion-exchange showed that a weakly acidic cation-exchange resin performed better than a strongly acidic cation-exchange resin did. The amount of solid residue under an alkalinity of 0 mg/L could be decreased by 92.9% compared with that of raw LLNC during evaporation. Both methods could alleviate scaling and enable the wide application of the MVR evaporation process in landfill leachate treatment.

中文翻译：

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蒸发法处理垃圾渗滤液防垢研究

摘要在垃圾渗滤液的机械蒸汽再压缩（MVR）处理中，蒸发器和热交换器的结垢是一个严重的问题。本研究探讨了这种结垢的原因，并提出了酸或离子交换预处理，以降低垃圾渗滤液纳滤浓缩物（LLNC）的碱度，以防止结垢。通过实验评价了这两种方法的可行性，并得出了适用的技术经济参数。LLNC中大量的HCO3-是结垢的主要原因。加酸实验和现场应用表明该方法可以防止结垢问题。加酸成本为0.18美元/吨。LLNC离子交换预处理表明，弱酸性阳离子交换树脂的性能优于强酸性阳离子交换树脂。碱度为0mg/L时，蒸发过程中固体残留量比原LLNC减少92.9%。这两种方法都可以减少结垢，使MVR蒸发工艺在垃圾渗滤液处理中得到广泛应用。